1. Field of the Invention
The present invention relates to apparatus for delivering humidified gases. In particular it relates to a humidifier arrangement for use in providing respiratory assistance to patients, for example in consumer Continuous Positive Airway Pressure (CPAP) delivery devices.
2. Summary of the Prior Art
Humidification systems are known which include a heater base and a disposable humidifier chamber which is fitted onto the heater base and within which a supply of water can be heated by the heater base. Air enters the humidifier chamber through an inlet air port in the roof of the chamber where it is humidified by the evaporation of water from the water supply before leaving the chamber through an exit port in the roof of the humidifier chamber.
Humidifier chambers of this type are also now used in compact and portable ventilation machines, for example machines intended for the home treatment of obstructive sleep apnoea (CPAP machines). Where the humidifier base is adapted for use with slide-on humidifier chambers, and the connection of the chamber to the machine is accomplished with a single sliding movement, the inlet air port is provided horizontally through the side of the chamber. Air enters the humidifier chamber through the inlet air port and the humidified air leaves the humidifier chamber into a breathing conduit through an exit port in the top of the humidifier chamber.
A disadvantage of these configurations is the need to disconnect the patient breathing conduit from the top of the humidifying chamber in a separate operation before removal of the chamber for the purpose of refilling. A further disadvantage of these configurations is that separate electrical wiring connections are required to make use of a heated respiratory conduit. Furthermore, in configurations such as these any contaminants or bacteria that enter the machine, such as a CPAP delivery to the humidifier chamber.